The two-fold purpose of this study is to determine how long-lasting are the effects of obsterical medication on infant psychophysiology, and to determine how long they continue to affect functions differentially. It has been reported that both anesthetics and analgesics depress the quality of infant test performance and that the drug produced dysfunction is not short-lived. Items from examinations at 4, 8, and 12 months of age that reflect CNS integrity will be analysed. The initial phase of the study is underway, beginning with an analysis of the frequency with which specific pharmacological agents were used during labor and delivery in a cohort of normal births in the CPP, preliminary to analyzing relationships between obstetrical medication and infant outcome variables.